Ribbon



Patented Apr. 19, 1949 RIBBON William Whitehead, Forest Hills, N. Y., assignor to. Celanese Corporation of America, a corporation of Delaware No Drawing. Application April 5, 1946. Serial No. 659,857

4 Claims.

This invention relates to a process for the treatment of narrow fabrics such as ribbons, and

relates more particularly to the treatment of ribbons woven of continuous filament, hightenacity, regenerated cellulose yarns, which ribbons after ink is applied thereto are employed as ribbons in various types of business machines or mechanical business aids.

Inked narrow fabrics, such as typewriter ribbons and tapes employed in cash registers, adding machines, and the like, are normally woven of silk or other textile material and the ribbon or marks off on to a sheet of paper or paper tape positioned beneath the ribbon whereby the character mounted on the key is reproduced on the paper. The life of said inked ribbons is limited due to the fact that the repeated impact of the striking keys not only efiects a permanent distortion of the threads of which the ribbon is woven but rapidly exhausts the ink composition with which said tape has been impregnated. I-Ieretofore, typewriter and similar ribbons having the best qualities in respect to printing clearly and having a long life in use have been made of silk. Others, having not as satisfactory properties, have been made of fine combed cotton yarns employing a good grade of cotton. Prior to the present invention, synthetic materials have not been as satisfactory, either demonstrating a shorter life or distorting too readily under the impact of the type of the typewriter or other printing machine.

It is, therefore, an important object of this invention to provide improved ribbons for use in typewriters, cash registers, adding machines and the like.

A further object of this invention is to provide a ribbon woven of continuous filament materials having a basis'of high-tenacity, regenerated cellulose yarns and filaments which will be highly resistant to distortion and wear and which will retain their ability to mark off or print clearly even after long and hard usage.

Another object of this invention is to provide a novel process for preparing ribbons for use in typewriters and the like'wherein a preliminary treatment is given to ribbons, woven of hightenacity, regenerated cellulose yarns and filaments, formed by stretching and then saponifylng yarns and filaments having a basis of cel- ,lulose acetate or other organic acid ester of cel- 2 lulose, whereby said ribbons are shrunk so that not only is the structure thereof strengthened and rendered more compact, but the ink acceptance of said treated ribbons is greatly improved. Other objects of this invention will appear from the following detailed description.

I have now found that the properties of narrow fabrics to be employed as typewriter ribbons, and the like, and woven of continuous high-tenacity, regenerated cellulose filaments may be substantially improved with respect not only to their service life but to their inking properties as well if said narrow fabrics are subjected to a suitable alkaline treatment prior to being impregnated with the desired inking composition. In accordance with the process of my invention, I subject ribbon materials woven of high-tenacity, regenerated cellulose yarns and filaments formed by stretching and then saponifying filaments having a basis of cellulose acetate or other organic acid ester of cellulose to treatment with an aqueous solution containing from 4% to 12% by weight of sodium hydroxide or other alkali metal hydroxide, such as potassium hydroxide, at a temperature of 15 to 25 C. for 2 to 60 minutes and then rinse, scour and dry the treated ribbons. Optimum results are achieved employing an 8% aqueous solution of sodium hydroxide at 20 C. and allowing it to act on the fabric for about 5 minutes. Alternatively, I may mechanically impregnate the ribbons with said alkaline solution and then rinse, scour and dry the treated ribbon. Not only does this treatment effect a very desirable shrinkage of the fabric whereby the structure is rendered more compact, but the ink acceptance of said fabric is substantially improved. The narrow fabrics treated in this manner, upon being inked, exhibit unusual resistance to the wear normally encountered by such inked ribbons when employed in cash registers, type-, writers, adding machines and other mechanical business aids. Furthermore, said inked fabrics retain their ability to print or mark off clearly and sharply for a longer period of time than fabrics woven of silk or. other textile materials.

Alternatively, wide fabrics may be woven of substantiallythe same fabric count, such fabric then subjected to the alkali treatment and slit to the desired width. Preferably such slit ribbons may be edged with gums, resins, cellulose esters, or cellulose ethers, applied from solution in suitable solvent to prevent ravelliug in use. Further, the wide goods may-be .woven, then slit, and the slit narrow goods subjected to the alkali treatment. Still further, wide or narrow goods may bases.

without being limited examples are given:

be woven from the stretched cellulose ester yarns and saponiflcation of the stretched yarns conducted in narrow ribbon or wide fabric form.

As stated, the high-tenacity, regenerated cellulose yarns of which said narrow or wide fabrics are woven are formed by stretching and then saponifying yarns having'a basis of cellulos acetate or other organic acid ester of cellulose. The yarns are stretched during a suitable stage in their manufacture and the yarns may be increased in length as a result of the stretch-.

rinsed directly, scoured and then can dried under light tension. After this alkaline treatment the ribbon contains 124 picks per inch.

ing operation to the extent of 200,,300, 500, or

even 1000 or 2000% of their original length. The yarns acquire a relatively high tenacity on being stretched, the tenacity being retained and in many instances enhanced by thesaponification' which effects a regeneration of the cellulose. The resulting high-tenacity, regenerated cellulose yarns are of great strength.

, The saponification of the stretched yarns as such, or in a fabric form, may be effected by means of any suitable basic agent. The saponifying agent may be inorganic in nature such as, for example, sodium hydroxide, potassium hydroxide, sodium silicate, ammonium hydroxide, sodium carbonate or other inorganic basic agents. Organic saponifying agents may also be employed such as, for example, methylamine, ethylene diamine, triethanolamine, or other organic The saponifying agent maybe employed in varying concentrations in aqueous, alcoholic, or aqueous alcoholic solutions. Advantageously, the saponifying bath may be at a temperature of 20 to 100 C. during the saponification process. For example, when aqueous solutions of sodium hydroxide are employed as the saponifying agent, the sodium hydroxide may be present in a concentration of from 0.1 to 5% by weight and saponification may be effected in from 1 to 60 minutes with the solution at a temperature of from 30 to 90 C. When employing aqueous solutions of sodium hydroxide as the saponifying medium, it is preferable to include a salt such as sodium sulfate or sodium acetate in said solution.

To effect the desired saponificati'on, the stretched yarns are led directly into the saponifying bath, the path through the saponifying bath being sufficiently extended and the speed at which the yarns pass through the bath being such that the yarns, under the conditions of both temperature and concentration employed, are completely saponified before leaving the bath. Speeds of to 100 meters per minute are satisfactory.

After the high-tenacity, regenerated cellulose yarns are woven into narrow fabrics or into broad fabrics which are then slit to the desired width, and the latter are subjected to the shrinking treatment described, after weaving,'or prior to or after slitting, the treated narrow fabrics are then impregnated with a suitable inking composition in th manner well known to the art. When dry, the ink-impregnated ribbons may be wound on spools suitabl for use in the type-of machine in which said inked ribbon is to 'be employed.

In order further to illustrate my invention, but

thereto, the following Example I yarns formed by stretching cellulose acetate yarns 10 times their original length and then The dried ribbon is then impregnated with a suitable inking composition. The ink acceptance of the ribbon following the alkali treatment is found to be greatly improved as compared to ribbons woven of the same material but which have not been given the alkali treatment prior to inking. In service as a typewriter ribbon, the inked hightenacity, regenerated cellulose ribbon is found to be extraordinarily resistant to wear and retains its ability to print or mark off clearly far longer than ribbons formed of other textile materials.

Example II A narrow fabric of an inch in width is woven of high-tenacity, regenerated cellulose yarns, obtained as described in Example I. The ribbon is woven in a plain weave and has a warp of 164 ends per inch of denier, 3 turns per inch, high-tenacity, regenerated cellulose yarn and a weft containing 112 picks per inch of 50 denier yarn having 3. turns per inch. The ribbon is skeined and the skein then immersed in an 8% by weight aqueous solution of sodium hydroxide at 20 C. for 5 minutes. The skein of ribbon is then rinsed, scoured and dried slack, after which the slack-dried ribbon is given a light warm calender. The dried calendered ribbon is then impregated with a suitable inking composition. The alkali treatment is found to im prove the ink acceptance of the ribbon substantially and to greatly improve the wearing qualities and life of the ribbon so that it is capable of printing or marking off very clearly for a much longer period of service than ribbons of the usual textile materials.

Example III A fabric is woven employing a warp containing 130 ends per inch and a weft containing 130 picks per inch of 64 denier, 3 turns per inch cellulose acetate yarn which has been stretched 10 times its original length. The fabric obtained is then completely saponified to yield a fabric of regenerated cellulose yarns by immersing the fabric in an aqueous bath containing 0.5% by weight of sodium hydroxide and 8% by weight of sodium acetate at 60 0., the'fabric being maintained therein for 30 minutes. The saponified fabric is rinsed well in water, cooled and centrifuged so that by weight of water remains thereon. The fabric is then padded at 20 C. with little or no tension employing an 8% aqueous solution of a resinous sealing composition and then impregnated with ink. Improved ink acceptance by the ribbons is effected and the inked ribbons are found to possess greatly improved wearing qualities.

It is to be understood that the foregoing detailed description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of my invention.

Having described my invention, what I desire to secure by Letters Patent is:

1. As a new article of manufacture, an inkimpregnated ribbon woven of high-tenacity, regenerated cellulose yarns formed by stretching and then saponifying yarns having a basis of an organic acid ester of cellulose, which ribbon has been shrunk to impart a compact structure thereto.

2. As a new article of manufacture, an inkimpregnated ribbon woven of high-tenacity, regenerated cellulose yarns formed by stretching and then saponifying yarns having a basis of cellulose acetate, which ribbon has been shrunk to impart a compact structure thereto.

3. Process for the production of ribbons adapted to be employed in typewriters, and the like, which comprises weaving a ribbon of hightenacity, regenerated cellulose yarns formed by stretching and then saponifying yarns having a basis of an organic acid ester of cellulose, subjecting said ribbon to a shrinking treatment employing an aqueous solution of an alkali metal hydroxide as the shrinking agent, and then impregnating said shrunken ribbon with an inking composition.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,830,620 Pelton Nov. 3, 1931 2,020,303 Dreyfus Nov. 12, 1935 2,053,767 Dreyfus Sept. 8, 1936 2,104,237 Neidich Jan. 4, 1938 2,243,877 Mann et a1 June 3, 1941 FOREIGN PATENTS Number Country Date 501,768 Great Britain Mar. 6, 1939 500,378 Great Britain Apr. 3, 1944 

